A power breaking apparatus for prevention of electrical shock breaks AC power supplied to electrical structures such as traffic lights, streetlights etc. if a leakage voltage is detected over a preset voltage or the electrical structures are inundated, thereby preventing electrical shock from inundation or leakage voltage. A plurality of inundation sensor rods of inundation sensing unit sense inundation of the metal posts. A plurality of leakage voltage sensor rods of the leakage voltage sensor sense leakage voltage. A power break signal generation unit generates ground current if the inundation sensing unit senses inundation or the leakage voltage sensor senses leakage voltage over a preset voltage and shots AC power to the ground if a predetermined time lapses. A zero phase sequence current transformers (ZCTs) detect the ground current. A leakage zero phase detector controls wiring breaker and a magnetic switch to break AC power according as the ZCTs detect ground current. The wiring breaker detects transient current to break AC power if the power break signal generation unit shorts AC power lines.